Originally posted by cubist
Yes, I'm upgrading my hard drive today, and plan to upgrade the CPU to 1GHz in a couple of weeks. Benchmarks of the 1GHz-upgraded Cube show it to be faster than the 1GHz LCD iMac, despite the Cube's slow 100MHz bus, because of the big L3 cache on the Powerlogix upgrade cards.
As for the video, the slot is a standard AGP 2X; the main problem is the physical size of most of the newer video cards. The Radeon 9000 and Geforce 4MX, for example, both have a bunch of blank area that makes them too tall to fit. We don't know why the manufacturers make their cards so tall, but the Cube's the only computer that has a height limit. I have a Radeon; many cubers have 2MX or 3MX cards, or Radeon 7500s.
Upgrading the cube does take time, care and reasonable mechanical skills. But it is basically a G4 tower in a small enclosure. The quality of construction is, IMHO, higher than most computers: the plastic is mainly on the outside; inside, it's nearly all metal. Quite a bit of precision-machined aluminum.